Part 10a

Question 1

digestive enzymes that are secreted by SI to partially hydrolyze proteins

Answer 1

trypsin, chymotrypsin

Question 2

prob of trypsin/chymo inhibitors?

Answer 2

as anti-nutritional factors, have risk of reducing dietary protein digestibility, contributing to nrg reduction and reduced bioavailability of essential a.a., possible toxicity

Question 3

where are T/C inhibitors found?

Answer 3

seeds of grain legumes (pulse/oilseed legumes), barley, squash, peanut, corn, potato

Question 4

functions of protease inhibitors in plants?

Answer 4

storage protein, defense mech against insects and herbivores

Question 5

how to inactivate these inhibitors?

Answer 5

moist heat treatments (100 degrees for 3-10 min), plant breeding and gene engineering to reduce lvls of these–>dry heat NOT effective

Question 6

toxicity of protease inhibitors?

Answer 6

reduced N and S absorb, reduce bioavailability, reduce GR, protein malnutrition, induce pancreatic hypertrophy, possible pancreatic cancer

Question 7

benefits of protease inhibitors?

Answer 7

genetically engineered into plants as biological control agent, and anti-carcinogenic (block ROS form, deprive cancer cells of a.a.)–>breast cancer treatment?, provide additional nutr value when denatured , role in AIDS treatment

Question 8

how does virus in AIDS become active?

Answer 8

thru aspartic acid protease

Question 9

also known as lectins, these are plant glycoproteins found in lots of seeeds, veg, fruit, virus, bacteria, moulds

Answer 9

hemagglutinins

Question 10

what is role of hemagluttinins?

Answer 10

not known, maybe in insect resistance, CHO storage, translocation

Question 11

how to inactivate hemagluttinin?

Answer 11

moist heat treatment

Question 12

toxicity of hemagluttinin?

Answer 12

resistant to stomach acid, bind to CHO in RBC–>agglutination–>anemia, kidney failure, bind to intestinal epithelial cells and interfere with nutr absorption, destroy villi, abnormal G and D, lesions permit intestinal bacteria to enter blood

Question 13

how is agglutination diff from clotting?

Answer 13

remain fluid, but hit kidney and can’t filter

Question 14

type of hemagglutinin used as poison

Answer 14

ricin (castor beans)

Question 15

glycoproteins that inhibit activity of mammalian alpha amylase in SI

Answer 15

amylase inhibitors

Question 16

what does alpha amylase do?

Answer 16

it hydrolyzes starch to produce gluc and maltose, which are readily absorbed

Question 17

amylase inhibitors found in:

Answer 17

kidney beans

Question 18

amylase inhibitors used as:

Answer 18

dietary suppplement for wt loss, GI lowering, diabetes treatment

Question 19

fxn of amylase inhibitors in plants?

Answer 19

insect resistance, impede starch digestion

Question 20

how to inactivate amylase inhibitors?

Answer 20

moist heat treatment

Question 21

prob of amylase inhibitors?

Answer 21

reduce bioavailability of important nrg for humans (v growth, organ wt changes (liver and pancreas)

Question 22

benefits of amylase inhibitors?

Answer 22

genetically engineered into plants as bio control agents to combat insect damage

Question 23

sulfur containing carbs contained in cabbage, cauliflower, broccoli, radish, mustard, rapeseed, turnips, brussels sprouts

Answer 23

glucosinates (thioglucosides)

Question 24

toxicity of glucosinates?

Answer 24

breakdown products are goitrogens

Question 25

what is goitrogens?

Answer 25

comps that cause ^ thyroid-->goitre, can't make hormone properly

Question 26

toxicity of nitriles?

Answer 26

acute toxicity (HCN)-->inhibit cytochrome oxidase required in e- transport-->organ damage; also bind to glutathione which inhibits ROS removal from cells; hemorrhaging and necrosis of adrenal cortex

Question 27

toxicity of isothiocyanates?

Answer 27

goitrogenic, inactivate enzymes in CHO metabolism path, react with sulfhydryl groups on proteases and make them inactive; cancer?

Question 28

____ isothiocyanate is a teratogen

Answer 28

allyl

Question 29

benefits of isothiocyanates?

Answer 29

phytochemical to inactivate carcinogens and protect cells from DNA damage, anti-inflammatory/antiviral/antibacterial, treat insomnia?

Question 30

toxicity of toxic a.a.?

Answer 30

enzyme inhibition as "suicide substrates"-->reduced cell transport of essential chem comps, probs with protein synth, help toxins move across BBB, reproductive disorders

Question 31

why is safety of free range questionable?

Answer 31

toxic a.a.s concentrated in seeds of forage grains/legumes-->transferred to humans when consume animal tissue

Question 32

examples of toxic a.a.?

Answer 32

mimosine (like tyrosine) and canavanine (like arginine)

Question 33

toxicity of beta-cyanoalanine

Answer 33

iathyrogen-->neurolathyrism (neuro disorder)-->musc rigid, crippling paralysis, death

Question 34

Brazil nuts have lots of these toxic a.a.

Answer 34

selenocysteine and selenomethionine

Question 35

selenium poisoning characterized by:

Answer 35

severe hemolytic anemia, kidney/liver/heart damage

Question 36

benefits of "toxic' a.a.?

Answer 36

anti-tumor (disrupt mitosis), treat Parkinson's (not beta-cyanoalanine), antiox (mimosine--phenolic), antimicrobial that is broad spectrum by impairing protein synth

Question 37

group of chem comps that may release HCN upon metabolism/decomp

Answer 37

cyanogens

Question 38

cyanogens naturally present in many plant species as _____

Answer 38

cyanogenic glucosides

Question 39

example of cyanogen found in cassava?

Answer 39

linamarin

Question 40

cyanogens found in almonds

Answer 40

amygdalin/laetrile

Question 41

how does cyanogenesis occur?

Answer 41

reactants come in contact only after phys. disruption of cells by bruising/cutting

Question 42

cyanide has strong affinity for ____ which causes disrupt cell resp-->death

Answer 42

cytochrome oxidase

Question 43

secondary metabolites derived from a.a. (basic or aromatic), like lysine/ornithine; tryptophan

Answer 43

alkaloids

Question 44

alkaloids found in about ___% of all plants

Answer 44

40

Question 45

toxicity of alkaloids?

Answer 45

strong anticholinesterase activity-->block Ach breakdown-->bradychardia; disrupt mem fxn in GI tract (lesions, hemorrhage, death); disrupt mitosis (growth, mutations, cancer); resp depression; cardiac arrest; neuromusc blockage (numb, weak)

Question 46

___ is 15% morphine

Answer 46

latex

Question 47

example of alkaloids in green potatoes?

Answer 47

solanine

Question 48

characteristics of solanine?

Answer 48

limited water sol, heat stable, cholinesterase inhibitor and causes GI lesions, ingestion symptoms include diarrhea, drowsy, vomiting

Question 49

example of alkaloids found in peel of green tomatoes

Answer 49

tomatine (glycoalkaloid)

Question 50

common alkaloid in coffee?

Answer 50

caffeine

Question 51

Denmark eat lots of ___

Answer 51

chocolate!

Question 52

what is acute lethal dose of caffeine?

Answer 52

10g

Question 53

what is caffeinism?

Answer 53

>500mg/day-->restless, anxious, irritable, musle tremor, insomnia, headache, GI probs

Question 54

caffeine blocks _____ receptors that is necessary for slowing down (breaking action, sleep and proper oxygenation)

Answer 54

adenosine (CNS)

Question 55

benefits of caffeine?

Answer 55

increased alert, vigilant, vigour, mood improve

Question 56

example of alkaloid in chocolate?

Answer 56

theobromine (very structurally similar to caffeine--just methyl grp)

Question 57

secondary plant metabolites synth thru acetate and shikimate pathways-->Phe and Tyr, naturally occuring polyphenolic comps with molecular mass 300-3000

Answer 57

tannins

Question 58

catechins and epicatechins found in:

Answer 58

fruits, tea, red wine, chocolate

Question 59

what is most abundantly consumed phenolic?

Answer 59

quercitin

Question 60

hydrolyzable tannins contain a central ____ + polyphenols

Answer 60

carbohydrate (usually D-glucopyranose) covalently linked to gallic acid residues

Question 61

what are condensed tannins?

Answer 61

don't contain CHO moiety (most abundant form in nature)

Question 62

example of condensed tannins?

Answer 62

proanthocyanidins, lignin (abundant cuz of stability)

Question 63

toxicity of tannins?

Answer 63

cross link with proteins/DNA/RNA-->structure change cause fxn change; carcinogenic; reduced wt gain and egg production (reduced protein absorption); digestive enzyme inhibition

Question 64

physical removal of tannins?

Answer 64

dehulling of grains

Question 65

chem treatment of tannins?

Answer 65

steam/alkali treatment (prob of nutrient destruction, colour formation, off flavour)

Question 66

tannin functions in plants

Answer 66

repaire damaged tissue, chem defense (metabolic arrest, cell div inhibition)

Question 67

why repair damaged tissue?

Answer 67

prevent microbial growth and insect infestation, reduce water loss, animals don't like astringent taste (rough, dry, chalky)

Question 68

tannins used to help:

Answer 68

gut health, antimicrobial for vag health, immune boost, liver health, ^ vision, wrinkle relaxer

Question 69

tannins found in this important food crop

Answer 69

sorghum

Question 70

benefits of sorghum:

Answer 70

cals, nutr, antioxidant

Question 71

limitations of sorghum:

Answer 71

rich in tannins, poor essential a.a. content esp. lysine

Question 72

sorghum used for:

Answer 72

porridge, unleavened bread: major processing step is boiling-->used as ethanol and animal feed for US

Question 73

new method for evaluating protein quality

Answer 73

DIAAS

Question 74

how reduce tannins ?

Answer 74

genetic engineering

Question 75

triterpenes (C30) that are norm covalently linked to CHO (glycoalkaloid) that exhibit foaming/emulsifying properties (surface active agent)

Answer 75

saponins

Question 76

saponins found in:

Answer 76

asparagus, beets, peanuts, potatoes, spinach, legumes

Question 77

toxicity of saponins:

Answer 77

powerful haemolyzing agents (RBC, liver, kidney necrosis)-->GI probs, vomit, cramps, fever, jaundice, paralysis, teratogen

Question 78

possible benefit of saponins?

Answer 78

; readily excreted intact cuz not absorbed, so possible toxic comp removal? Not issue in humans really

Question 79

other naturally occuring toxic comps in foods?

Answer 79

gossypol, sesamol, eugenol, coumarin